In many insulated containers, rigid materials are combined with insulating materials to form containers having insulating properties. By use of such containers, product suppliers may ship perishable products refrigerated or at room temperature, live or frozen, to customers while controlling the environment in which the perishable products are placed, or while simply extending the useful life of such products before they spoil. Examples of such uses for containers used in shipping include the shipment of fresh fish, in which a customer has requested that the product not be frozen, fresh flowers, around which a cool and moist environment should be maintained, and frozen tissues for research. With all such products, maintenance of constant, or low temperature, will help preserve freshness and quality of the products, or extend the useful life of the products, and often thereby increase the distance over which such products may be shipped, as extending the time during which a product is preserved extends the time for shipment during which such product may reach its destination.
In other insulated containers of this same general description, the usefulness of the container is in preserving the temperature of foods or beverages used in picnics, family outings, ball games, and other recreational activities.
Containers of this type which have been successfully employed for these purposes include insulated contains made from cardboard and individual pieces of insulating material, such as styrofoam or other lightweight foam type insulation. This type of container is often constructed by gluing the individual pieces of the insulating foam material to the interior surfaces of the cardboard, which is formed as a box, or by inserting separate foam pieces to insulate each container surface. While this type of container offers advantageous high thermal resistance, cutting and gluing pieces of foam to construct the finished container requires substantial assembly time, with the result that containers formed in this way are expensive to assemble.
Containers of this type also include insulated containers made of plastic foam. Typically this type of insulated container is composed of expanded polystyrene foam, which is formed in a mold to the desired shape, in which the foam provides the dimensional structure of the container as well as the thermally insulative barrier. In some cases, additional corrugated pieces may be used to provide additional structural support. While this type of container also offers high thermal resistance and, in addition, ease of assembly, the resulting container is rigidly set in its final form at the time of manufacture, with the result that this type of container requires substantial floor space and volume to store and transport prior to, during, and after use. Moreover expanded polystyrene is generally considered to have a high impact on the environment as undesirable byproducts are released upon its manufacture. In addition, polystyrene decomposes slowly, and, due to its airy and bulky nature, it occupies a large volume in land fill disposal sites.
Another type of container generally suited for shipment of perishable products consists of generally rigid walls made of corrugated cardboard or other suitable material, to which is bonded a flexible, sealable, insulative material having bubbles of air entrapped therein to provide thermal insulation. One form of such material is commonly referred to as "bubble wrap," however rubber or plastic foam or other material having the characteristics described herein may be employed in the present invention. The flexible material may have a reflective surface, or an additional layer of flexible reflective material, attached to the rigid walls or flexible, sealable, insulative material, to increase thermally resistant efficiency. While this type of container is well suited to some applications, and has distinct advantages over other type of insulated containers, the containers of this type appearing in prior art do not allow for easy assembly by a user, with resulting savings in time and costs, and do not result in water-tightness in the container for retention of fluids, or runoff from melting ice, associated with the products shipped.
It may be appreciated, in light of the foregoing discussion, that there is a need for an environmentally friendly, affordable, insulated container, suitable for shipping perishable products, and suitable for providing convenient temperature control when conducting recreational activities, where the container is easy to manufacture, thermally resistant, water-resistant and watertight, lightweight, compact prior to assembly, and easy to assemble by a user. The present invention is directed precisely to such useful characteristics.
A number of schemes have been devised to accomplish one or more of the goals set forth above. These schemes include single-piece and multi-part containers of cardboard, foam, and plastic flexible, sealable, insulative material materials. Various designs and configurations for such apparatus include:
U.S. Pat. No. 3,754,642 to Stidolph, which discloses a waterproof container for shipping and displaying perishable products.
U.S. Pat. No. 4,682,708 to Pool, which discloses a paperboard shipping container having non-rigid, foamatious insulating material, and a plastic bag placed between the paperboard and insulating material.
U.S. Pat. No. 4,889,252 to Rockom et al., which discloses an insulated container formed of corrugated paperboard and a layer of flexible material having air bubbles and foil.
U.S. Pat. No. 5,009,326 to Reaves et al., which discloses an insulated multi-part container of corrugated cardboard, folded and stapled to form an enclosure, with one-piece insulated liner.
U.S. Pat. No. 5,638,978 to Cadiente, which discloses an insulated waterproof container for the shipment of produce.
In the above-noted inventions, and in other prior art, cardboard, when formed into a box, is a popular material in the shipping industry because it is inexpensive and relatively light weight when compared to its strength. As a result, insulated containers composed in part of cardboard or paperboard help minimize shipping costs. However, cardboard alone is not suitable in those applications in which temperature should-be maintained within the container, and it is not suitable in those applications where the contents of the container is a fluid, such as water, or where fluid is important to preserving the contents.
Prior efforts at achieving a suitable container for such purposes have therefore focused on configurations and materials which have desirable characteristics when used in combination with cardboard, or which have both rigidity and such characteristics when used without cardboard. As a result, various inventions of the prior art, such as those of the above-noted patents, employ combinations of various insulating materials, whether rigid or flexible, and water-tight or water-resistant layers or barriers. A variety of insulating and water-resistent effects may be achieved where these materials are combined and formed as directed by prior art. Thus, good insulative properties are achieved by containers utilizing preformed foam, however preformed foam does not allow compact storage, while foam sheets requires expensive assembly and cannot achieve water-tightness. In the alternative, cardboard with flexible plastic bubble sheets may be easy to manufacture, however most such arrangements are not water-tight, or are time consuming for a user to assemble if stored and shipped in compact, "knock down" form. In addition, the construction of such arrangements are somewhat expensive because multiple sheets are required.
The present invention is directed to combining desirable features to achieve an insulated container suitable for shipment or storage of a wide variety of products, particularly perishable products. While the devices disclosed in prior patents fulfill their respective objectives, prior patents and inventions do not describe or suggest an insulated, water-tight container, easy and inexpensive to manufacture, compact in storage and shipment, and quickly reformed by a user to produce the final container having the desirable characteristics mentioned herein.